Ripper assemblies are commonly used to loosen hardened ground and break up rock formations. In such operations, a ripper shank having a tip mounted on a lower end is pulled, and sometimes additionally pushed, through the ground with sufficient force to break up the hardened ground or rock. Fracture zones in the rock, and large rocks randomly distributed in hardened ground defect the tip away from a true forward direction, imposing significant twisting forces on the tip of the ripper shank. The impact twisting forces imposed on the ripper tip are transmitted through the ripper shank to the structure supporting the ripper implement.
The upper end of ripper implement support structures is generally attached to pitch control cylinders which control the pitch, or attack angle, of the ripper tip with respect to the ground. Repeated severe twisting impact shock forces on the ripper tip adversely affect the integrity of the support structure, to the point that weld joints fail and the ripper assembly becomes inoperable. For example U.S. Pat. No. 4,991,659, issued Feb. 12, 1991 to Visvaldis A. Stepe, et al., for a RIPPER ASSEMBLY WITH PITCH CONTROL AND INTEGRAL FRAME AND PUSH BLOCK, and assigned to the assignee of the present invention, discloses a ripper assembly in which the pitch control cylinders are pivotally attached by universal brackets mounted on the sides of the ripper shank support housing. Repeated twisting impact shock forces on the ripper tooth can cause failure of the welded joint between the universal brackets and the ripper support housing. The present invention is not only directed to overcoming the problems set forth above, but also to providing a ripper assembly capable of storing a portion of the twist forces and use that stored energy to return the tip to its original orientation.